Milch und K?se

Ohne Zusammenfassung     

Local transverse arch repair for type A aortic dissection

BACKGROUND: The management of retrograde dissections originating from the transverse arch is controversial. Although replacing the ascending aorta is clearly beneficial, the appropriate approach to the management of the arch tear is not as apparent and ranges from no intervention to total arch replacement. METHODS: Three patients presented with acute (n = 2) or subacute (n = 1) aortic dissection, with tears involving the transverse arch. All underwent local transaortic pledgeted suture repair of the arch tears during hypothermic circulatory arrest, as well as graft replacement of the ascending aorta. RESULTS: Circulatory arrest times ranged from 12 to 15 minutes (transaortic arch repairs alone) to 48 minutes (transaortic arch repair and open distal graft anastomosis). Postoperatively all patients awoke within 12 hours and subsequently did well neurologically. CONCLUSIONS: In the face of a type A dissection with an entry in the transverse arch, local transaortic repair with concomitant ascending aortic replacement represents a viable middle ground between no arch intervention and lengthy arch replacement. Huge entry tears or aneurysmal arch enlargement would preclude such an approach.     

Assessment and evaluation of the radiological situation in the late phase of a nuclear accident

An overview of existing approaches on assessing and evaluating the radiological situation in the late phase of a nuclear accident is given in this paper. Special attention is paid to the weak points of existing approaches and to problems to be solved in the future. Assessment of the radiological situation can be based on both monitoring data and model predictions. Approaches have been developed for many years in both categories and have meanwhile reached some kind of maturity and also operational applicability. Nevertheless, some areas exist where significant improvements could be achieved in the near future, e.g. by combining monitoring data and model predictions, by improving the modelling of urban areas or by improving existing radioecological models.     

Silicon for thin-film transistors

We are standing at the beginning of the industrialization of flexible thin-film transistor (TFT) backplanes. The two important research directions for the TFTs are (i) processability on flexible substrates and (ii) sufficient field-effect mobilities of electrons and holes to support complementary metal insulator semiconductor operation. The most important group of TFT capable semiconductors are the several modifications of silicon films: amorphous, nanocrystalline and microcrystalline. We summarize their TFT properties and their compatibility with foil substrate materials.     

Relative leaching and aquatic toxicity of pressure-treated wood products using batch leaching tests

Size-reduced samples of southern yellow pine dimensional lumber, each treated with one of five different waterborne chemical preservatives, were leached using 18-h batch leaching tests. The wood preservatives included chromated copper arsenate (CCA), alkaline copper quaternary, copper boron azole, copper citrate, and copper dimethyldithiocarbamate. An unpreserved wood sample was tested as well. The batch leaching tests followed methodology prescribed in the U.S. Environmental Protection Agency toxicity characteristic leaching procedure (TCLP). The wood samples were first size-reduced and then leached using four different leaching solutions (synthetic landfill leachate, synthetic rainwater, deionized water, and synthetic seawater). CCA-treated wood leached greater concentrations of arsenic and copper relative to chromium, with copper leaching more with the TCLP and synthetic seawater. Copper leached at greater concentrations from the arsenic-free preservatives relative to CCA. Arsenic leached from CCA-treated wood at concentrations above the U.S. federal toxicity characteristic limit (5 mg/L). All of the arsenic-free alternatives displayed a greater degree of aquatic toxicity compared to CCA. Invertebrate and algal assays were more sensitive than Microtox. Examination of the relative leaching of the preservative compounds indicated that the arsenic-free preservatives were advantageous over CCA with respect to waste disposal and soil contamination issues but potentially posed a greater risk to aquatic ecosystems.     

Relationship Between the Different Aspects Related to Coffee Quality and Their Volatile Compounds

This paper provides, for the first time, an overview of different aspects related to the quality of coffee beans and their volatile fractions: species/cultivars, geographic origins, bean defects, and types of beverages, processing, roasting, and storage. In other words, it concerns the complex relation between the quality of coffee seeds and their volatile components. It is an overview of 48 articles and considering 6 different aspects related to the quality of coffee and its aromatic fraction. The greatest numbers of published papers concerned “species and cultivars” and “defective seeds,” both with 11 articles cited, followed by “storage” with 10 articles. Many aspects still require greater clarification, including the effects of geographical origin, processing, and roasting. Other issues that are better understood include the effects of species type, defective seeds, and storage conditions. Another topic that has received very little attention is the question of the existence of many different coffee cultivars within each species, which we believe should be further investigated, given that this can significantly affect the quality of the final beverage. Meanwhile, with the growing technological development in the areas of science and agriculture, there are many other aspects to be studied (or revisited), and the field of the aromatic quality of coffee provides ample opportunity for scientific investigation.     

Bitterstoffe beim Erhitzen von Saccharose, Maltose und Prolin 2. Mitteilung

Summary In addition to the mono- and dipyrrolidinohexosereductones described recently (Z Lebensm Unters Forsch (1984) 178:356) two further bittertasting compounds were isolated from heated mixtures of proline and sucrose (molar ratio 3: 1, 190 °C, 30 min) and also synthesized, namely 2,3-bis-(1-pyrrolidinyl)2-cyclopenten-l-one and 2,3-bis(1-pyrrolidinyl)-5methyliden-2-cyclopenten-l-one. The recognition thresholds (mmol/1) are 0.15–0.25 and 0.06–0.12 respectively. Both compounds have a burning bitter taste character. From a maltose-proline reaction mixture 2--glucosyl-5-hydroxy-5-methyl-4-piperidinyl-2-cyclopenten-1-one was isolated. When the dihydroxypyranone VI was heated with proline, 2,5-dihydroxy-5-methyl-4-prohnyl-2-cyclopenten-1-one and the cyclopent(b)azepinones XI and XII were among the compounds formed. These compounds also have a bitter taste character.Zusammenfassung Zusätzlich zu den kürzlich beschriebenen Mono- and Dipyrrolidinohexosereduktionen (Z Lebensm Unters Forsch (1984) 178:356) wurden zwei weitere bittere Verbindungen aus erhitzten Mischungen von Prolin and Saccharose (Molverhältnis 3:1, 190 °C, 30 min) isoliert and synthetisiert. Es handelt sich um 2,3-Bis-(1-Pyrrolidinyl)-2-cyclopenten-1-on und 2,3-Bis-(1-Pyrrolidinyl)-5-methyliden-2-cyclopenten-1-on. Die Erkennungsschwellenwerte (mmol/1) sind 0,15-0,25 and 0,06-0,12. Beide Verbindungen haben einen brennend-bitteren Geschmack. Aus einem Maltose-Prolin-Umsetzungsgemisch gelang die Isolierung des 2--Glucosyl-5-hydroxy-5-methyl-4-piperidinyl-2-cyclopenten-1-ons. Bei der Reaktion des Dihydropyranons VI mit Prolin wurden u. a. das 2,5-Dihydroxy-5-methyl-4-prolinyl2-cyclopenten-1-on sowie die Cyclopent(b)azepinone XI and XII gebildet. Diese Verbindungen sind ebenfalls mehr oder weniger stark bitter.     

Einflu? von Glasgewebeeinlagen auf Biegung und Querzug von Spanplatten

Ohne Zusammenfassung     

A hierarchical modeling approach for risk assessment in developmental toxicity studies

Within the past decade, there has been an increasing interest in the problem of joint analysis of clustered multiple outcome data, motivated by developmental toxicity applications. Typically, a toxic insult early in gestation may result in a resorbed fetus or a fetal death. If however the fetus survives the entire gestation period, growth reduction such as low birth weight may occur, or can exhibit a malformation. Ideally, a model should take the complete hierarchical structure of the data into account. So far, however, one has tackled the challenges in this setting only partly each time making different restricting assumptions (e.g., restriction to viable fetuses only). In addition, because of genetic similarity and the same treatment conditions, offsprings of the same mother behave more alike than those of another mother. Thus, responses on different fetuses within a cluster are likely to be correlated. The ultimate scientific question requires assessing the full effect of dose administration, not only in the malformation and weight outcome, but also in the death outcome. A hierarchical Bayesian method is proposed to this effect. Such a model can serve as a basis for quantitative risk assessment.     

Bestimmung des Endotoxin-Gehalts in Eiprodukten mit Hilfe eines miniaturisierten chromogenen Limulus-Tests

Zusammenfassung Die Eignung eines chromogenenLimulus-Tests zur Bestimmung des Endotoxin-Gehalts in Eiprodukten wurde gepruft. Dabei zeigte die Analyse verschieden stark bakteriell belasteter Volleimassen eine deutliche Korrelation zwischen Endotoxin-Konzentration und Gesamtkeimzahl (6 x 10⁴ cfu x ng^–1 Endotoxin) Bowie der Anzahl vonEnterobacteriaceen (7x10² cfu x ng^–1 Endotoxin). Vergleichbare Ergebnisse konnten auch mit Eigelb- und Eiweilßproben erzielt werden. Der Endotoxin-Nachweis wurde durch Hitzebehandlung (65 °C, 60 min) nicht beeinflußt. Endotoxinfreies steriles Volleimaterial hatte bis zu einer Konzentration im Testansatz von 10 mg x ml^–1 keinen Einfluß auf das Mcßergebnis. Im vorliegenden Bericht wird eine miniaturisierte Version des Testverfahrens vorgestellt, die im Mikro titerplatten-System durchgeführt werden kann.

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Determination of endotoxin in egg products with a miniaturized chromogenic Limulus test

Summary A chromogenicLimulus amoebocyte lysate assay was applied to monitor endotoxin concentration in egg products. Analysis of differently contaminated whole egg probes revealed a strong correlation of endotoxin concentration to total bacterial count 6 x 10⁴ cfu x ng^–1, where cfu=colony-forming unit) as well as to number ofEnterobacteriaceae (1 ng/7 x 10² cfu). Similar relations were also found for egg white and egg yolk probes. A significant influence of heat pretreatment of egg probes (65° C, 60 min) on endotoxin detection could be excluded. Up to a concentration of 10 mg x µl^–1 endotoxin-free whole egg material did not interfere with the test system. A miniaturized version of the chromogenicLimulus test, which can be carried out in microtiter plates, is described.